const myHeading = document.querySelector("h1");
myHeading.textContent = "我在杉达很困。";
let myVariable;
let iceCream = "chocolate";
if (iceCream === "chocolate") {
  alert("我最喜欢巧克力冰淇淋了！");
} else {
  alert("但是巧克力才是我的最爱呀……");
}